The battle for the Senate is ramping up a little more than one year before Election Day, with candidate and primary fields getting more settled by the month. 

Democrats remain hopeful of their chances to keep hold of their slim majority despite a difficult map for the party in 2024, but Republicans have prime opportunities to knock off incumbents and pick up seats in states won by former President Trump in the 2020 and 2016 presidential elections.

Here are the top five Senate races to watch at this point.

West Virginia 

No matter how you slice it, the road to reelection for Sen. Joe Manchin (D-W.Va.) — if he decides to run — is a treacherous one as the political universe awaits word on whether he will seek a third full term in the Senate. 

The West Virginia centrist is expected to decide either late this year or shortly before the January filing deadline, just as he did in 2018.

He faces an uphill climb no matter how you look at it. Not only would he be running in a presidential year that could see Trump — who won the state by 39 points in 2020 — atop the ballot for Republicans, but he would likely be doing so against sitting Gov. Jim Justice (R). 

All of that is a recipe for trouble, which Democrats readily acknowledge even though they refuse to discount Manchin’s ability to connect with the electorate. 

“West Virginia is the one that … worries us the most,” said John LaBombard, a former top aide to Sen. Kyrsten Sinema (I-Ariz.) and former Sen. Claire McCaskill (D-Mo.), and a Democratic strategist with ROKK Solutions. “It’s hard for anyone to make the decision to run again when the path is so challenging. Even for Sen. Manchin, it would be a challenging path.”

“I would not count him out,” LaBombard cautioned. “I think people make the mistake of betting against Manchin.” 

According to a survey taken last month, Justice holds big leads over Manchin in a general election match-up and Rep. Alex Mooney (R-W.Va.) in the primary, and Republicans could not feel more bullish about him. 

“Justice is a juggernaut,” one GOP operative said, wishing those challenging him “good luck.”

Montana 

Sen. Jon Tester (D-Mont.) is awaiting his eventual GOP challenger in a push for a fourth term next year, with questions surrounding whether Rep. Matt Rosendale (R-Mont.) will end up launching a second consecutive bid for the seat. 

Tester faces many of the same potential issues as Manchin: a tough environment with Trump atop the GOP ticket and a deep red state that forces him to rely on the support of independents and some Republicans on top of his Democratic base.

The big difference for Tester is the unpredictability of his GOP opponent.

National Republicans have thrown their full weight behind businessman Tim Sheehy, who they argue is uniquely set to take on Tester. But in order to do that, he’ll have to defeat Rosendale — if the conservative follows through with a statewide run that he’s been teasing for months.

Political watchers argue that time is running low on Rosendale to launch a bid, especially considering that Sheehy has been up on the airwaves since July.

“Is he ever actually going to announce?” the GOP operative said. “Like, what are we doing here?” 

Adding to the questions is Rosendale’s latest dalliance with the political spotlight after it emerged that he clamored for a small House GOP majority — angering many Republicans — and voted with seven others to oust former Speaker Kevin McCarthy (R-Calif.) from his post. 

Rosendale’s battles with McCarthy have not helped his fundraising. He posted a paltry $334,000 in the third quarter, a total dwarfed by both Tester, who raised more than $5 million, and Sheehy, who raised $2.8 million. 

Rosendale has signaled he believes he has time to make a decision. He said in a recent interview that he is ready to greenlight a run as late as the state’s filing deadline in March.

“We’re still making considerations. … I’m pleased [with] the support that I have across the state. I can’t ignore that. But it’s a very big decision,” he told The Hill. “We’ve got plenty of time to make that decision. … I’ve got plenty of time. I mean, I truly do.”

Ohio

Rounding out the holy trinity of Senate contests this cycle, Sen. Sherrod Brown (D-Ohio) is gearing up for what is expected to be the toughest contest of his career.

Brown won his 2012 and 2018 contests by 6 and 7 percentage points, respectively, but is likely looking at a much closer affair this time around as he grapples with a state that has grown decidedly more red since he last faced the voters.

The incumbent Democrat is doing his part, posting a $5.8 million fundraising quarter, but he is running into major headwinds. 

Unlike the last time he ran — in a presidential year when then-President Obama won the state — Brown will have to do the heavy lifting, as Democrats believe it is unlikely President Biden’s operation will devote major resources to the state.

Who Brown will face is a major question.

Ohio Secretary of State Frank LaRose (R), state Sen. Matt Dolan (R) and businessman Bernie Moreno are battling it out for the Republican nod. Dolan and Moreno each reported roughly $4 million raised in the third quarter, including $3 million from their own pockets.

LaRose is the lone non-self-funder on the GOP side, prompting questions over whether he can keep pace with the two financially. None of the three are giving Republicans boatloads of confidence heading into one of the cornerstone contests on the map.

“This is the problem with having a bunch of B- and C-tier candidates,” the GOP operative said. 

“Brown will never be comfortable in his election cycle, and he has no right to be comfortable in a state Trump will win by 6 to 8 points,” the operative continued. “But the reality is he’s probably got the best draw of all these super vulnerable candidates no matter which of these three Republicans make it out.”

Arizona

Perhaps the most enigmatic Senate contest became a little more clear last week when Kari Lake rolled out her campaign, likely cementing the GOP nomination in the fight for Sinema’s seat.

The main question on the GOP side is whether Lake’s rebrand is real or not. During her launch event early last week, Lake sounded like a different candidate from the one during and after her losing 2022 gubernatorial bid that commonly featured talk about a stolen election and Lake infamously telling McCain Republicans in the state to “get the hell out.” 

Instead, she extended an olive branch to Biden’s supporters as she seeks to broaden her base of support. 

“I don’t think you’re a threat to democracy. You are a citizen just like me,” Lake said. “And I know you’re struggling as well. We’re all struggling — there’s not a gas pump out there for Republicans and one for Democrats.”

According to sources, some Republicans are buying into it — for now — and cite a more buttoned up operation than the shoestring one she ran in 2022. 

“She’s taking that very seriously. She’s focusing on the main thing and sprinting toward victory,” a second GOP operative said, adding that includes building support from Arizonans and “no more virtue signaling” to people in Washington.

A source familiar with strategy at the National Republican Senatorial Committee said that it has not ruled out endorsing her. 

However, her path to victory could be much more different if Sinema continues on course with an independent bid against her and Rep. Ruben Gallego (D-Ariz.).

“I can’t guarantee anything. It’s crazy,” LaBombard said of a possible three-way race. 

Pennsylvania

Unlike any of the other states on this list, the GOP at almost every level has unified behind David McCormick in his second run in as many cycles to take on Sen. Bob Casey (D-Pa.) next year. 

McCormick made his bid official last month and has quickly coalesced the party behind him, including the entire delegation of House Republicans and the state party, both of which endorsed him shortly after his announcement. Republicans believe McCormick is a far superior candidate to the one that failed against Mehmet Oz last year and that he has cleaned things up where they needed to be. 

“He understands what went wrong last time,” the first GOP operative said. “Casey is better than the average Pennsylvania Democrat, but Dave’s not going to have a resource problem. If he is able to effectively get his message right and not be pulled in too many directions like he was last time, this is a state that’s going to come down to tens of thousands of votes on the presidential level, and we know it’s possible that you can split tickets in Pennsylvania to the degree that he would need to.” 

The operative said that McCormick’s ideal scenario is the map that put former Sen. Pat Toomey (R-Pa.) across the finish line in 2016: outperform Trump in the suburbs and hold serve where the ex-president is strong throughout the reddest parts of the state. 

However, taking on Casey is a massive challenge for Republicans, and one that has not been successful ever since he knocked off former Sen. Rick Santorum (R-Pa.), formerly the No. 3 Senate Republican, in 2006. The three-term senator has notched resounding victories in each of his reelection bids.

A recent Quinnipiac poll shows this might happen again, with Casey leading by a 6 point margin — 50 percent to 44 percent — over the former Bridgewater Associates CEO. 

Emily Brooks contributed.

–Updated at 8:38 a.m.